Atomizing oil burner



Aug. 30, 1932. w. A. BABB ATOMIZING OIL BURNER Filed June 15, 1951 Inventor Patented Aug. 30 1932 UNITED STATES PATENT. OFFICE WALTER A. BABB, OF GLENDALE, CALIFORNIA ATOMIZING om BURNER Application filed June 15, 1931. Serial No. 544,319.

complete combustion of the oil is securedand a clean sootless flame produced.

Still another object is to provide a burner that can be readily adjusted to deliver different amounts of atomizing fluid.

Atomizing oil burners can be classified broadly into two types, namely, internal atomizing and external atomizing. In the first type, the oil is mixed with the atomizing fluid and thoroughlybroken up, within the body of the burner. Some difficulty has been encountered in operating this type of burner in that the pressure of the atomizing fluid, being usua'lly much greater than the pressure of the oil delivered through the burner, sometimes prevents the oil from feeding into the burner. The external atomizing type of burner has come into general use chiefly because it is not subject to this objectionable feature, the'oil being discharged from one orifice in the burner and the atomizing fluid being discharged from another orifice so that the two streams meet outside of the burner. A weakness of this type of burneris that it is sometimes diflicult to thoroughly commingle the oil and atomizing fluid and thus break the oil into sufliciently fine particles to produce rapid and complete combustion thereof.

In accordance with the present invention, thorough atomization of oil is produced in an external atomizing burner by discharging the oil from a narrow slot so that it issues in the form of a. very thin sheet and then discharging steam or air at high velocity into the sheet of oil from both sides. F urthermore, I producethis result with a very simple apparatus which will now be described in detail with reference to the drawing in which- Figure 1 is an end view of my burner;

encloses the latter.

Figure 2 is a longitudinal section of the burner in the plane II, II of Figure 1;-

Figure 3 is an inside view of the burner head shown in Figure 1; Figure 4 is a sectional view in the plane IV, IV of Figure 2;

Figure 5 is a sectional view in the plane V, V or Figure 2; and

Figure 6 is a sectional view in the plane VI, VIof Figure 2.

I Referring to Figure 2, the burner comr prises essentially three main portions, namely, a tip or nozzle portion 1, a base 2 and a sealing plate 3 positioned between the base and tip portions. Oil is supplied to a passage 4 in the base portion by an oil pipe 5, and steam, air, or other atomizing fluid is supplied to an outer passage 6 in the base portion 2 by a pipe 7. In the embodiment shown, pipe 7 is much larger than pipe 5 and This form of construction is desirable when utilizing steam as the atomizing fluid because the oil in pipe 5 is preheated by the steam in pipe 7 before it gets to the burner. However, this form of construction is not essential to my invention, and if desired, the oil and atomizing fluid may be delivered to the base 2 by tubes not concentrically positioned with respect to each other.

The base 2 is provided with a tubular extension 10 on its outer end and the inner surface of this tubular extension is threaded to receive the tip 1. Within the tubular extension 10 and positioned therebelow is a shoulder 11. The surface of shoulder 11 and the outer surface of the central tubular portion 12, which is attached to the base 2 by a web 13 (shown in Figure 6) are ground to a plane surface. Disk 3, both sides of which are round to parallel plane surfaces, fits 'withln the tubular extension 10 and forms a gas tight joint with the ground surfaces of shoulder 11 and the tubular extension 12.

The tip 1 which is provided with threads on its outer circumference screws into the tubular extension 10 and fits tightly against disk 3. Referring to Figure 3, tip portion 1 has an outer rim 14 and an inner circular ridge 15 which are ground to lie in the same plane surface so that they fit snugly against the outer ground surface of disk 3 and form gas ti ht connections therewith. As shown in Figure 5, disk 3 has several apertures 16 5 formed adjacent its outer edge to permit the passage of atomizing fluid from passage 6 in the base 2, to a circular passage 17 in the tip portion, and it also has a passage 18 in the center to permit the flow of oil from the passage 4 in base 2 to oil passage 19 in the tip lie parallel to that plane. Positioned in each passage 21 is a bushing 22 having an outwardly extending flange 23 at its inner ex- I I tremity and being closed at the opposite end and provided with a transverse slot 24. The

' inner ends of passages 21 are reamed out to a larger diameter toprovide room for the flanges 23 on the tubes 22, and washers are positioned beneath flanges 23. The slots 24 are positioned substantially at the outer surface of the tip 1 and the effective size of slots 24, which form the discharge orifices for the atomizing fluid, may be varied by using washers 25 of different thickness; thus if washers of greater thickness than those illustrated are used, bushings 22 will not project so far from. 5 the front surface of tip 1 and the orifices 24 will be partially closed by the portions of tip 1 which project over the slots 241 As shown in Figures 1 and 2, the outer surface of tip 1 is ground to a smooth concave surface extending from orifice 24 out to the edges of slot 20. The streams of atomizing 'fluid discharged from slots 24 follow the concave surfaces 26 andare gradually deflected until'at the time they leave the edges of slot 20they are flowing substantially parallel to the walls of slot 20. These streams of atomizing fluid pick up the oil as it issues from the slot and break it into an exceeding- 1y fine mixture which burns completely in an incandescent flame A With the apparatus as described it is found that a relatively long flame is produced.

..Thisis' not objectionable in some types of furnaces, for instance, in return tube boilers. There are other installations, however, in

which a broad, fan-shaped flame is desirableandunder those conditions I provide in my burner a baflle 27 whichis supported between 5 disk 3 and tip 1 by a spring28 attached to a baflle stem 29. Spring 28 fits snugly within the passage 4 in base 2. A groove may be formed about the inner circumference of the tubular member 12 adjacent to disk'3 into whichthe last turn of spring 28 fits, but this burner passage is not essential and may be omitted. When no oil is supplied to the burner spring 28 holds bafie 27 against disk 3 thus closing the .central passage 18 through the disk, but as soon as oil is admitted to the burner, the

pressure lifts baflle 27 away from disk thus permitting the passage of oil around.

the edges'of the baflle 27. As may be noted from Figure 3, passage 19 is oval in crosssectional area, being of greater width in a direction parallel to slot 20 than at right angles thereto.

As shown in Figure 2, the width of passage 19 along its short diameter is somewhat less than the diameter of baflle 27 so that when baflie 27 is forced outward by the oil pressure in passage 4 it rests against shoulders 30 adjacent the edge of passage 19. In this position, oil can flow past baflie 27 only on the sides adjacent the outer ends 31 (re ferring to Figure 3) of passage 19 so that more oil issues from the edges of slot 20 than from the central portion. This results in a shorter, more spreading, flame than is attained without the use of baffle 27 and is desirable as pointed out above in certain installations where a long flame is objectionable.

Although spring 28 on baffle 27 is relatively weak and yields to moderate oil pressure in the passage 4, it serves to close the passage 18 when the oil supply has been shut off and thus prevents oil left in pipe 5 and in the y from dripping out through the burner.

As heretofore pointed out, one of the chief advantages of my burner is'its simplicity of manufacture and assembly. Those machining operations that are necessary are simple and may be quickly performed without the exercise of special care. There are only five essential parts to the burner head, namely, the base 2, the disk 3, the tip 1, and the bushings 22. This, obviously, simplifies the assembling operation. The bushings' 22 fit snugly in the holes 23, and may be inserted or removed without loosening any nuts, screws, or bolts. It is practicable to eliminate any special locking means for holding,

the bushings in position because they, are urged outward by the steam pressure in passage 17 during operation of the burner.

I claim: c

1. An atomizing burner head comprising a body portion having flattened sides concavely tapered to the end, an oil discharge slot in said end and a pair of atomizing fluid orifices one on each side of said flattened end, directed to discharge atomizing fluid along the concave surfaces toward said oil discharge slot.

'2, An atomizing oil burner head comprising a body portion having an oil discharge slot in the end thereof and concave sides leading away from the edges of said slot, a pair of atomizing fluid dischar e orifices at the separate passages for connecting said slot and bases of said concave sides irected inwardly said orifices to separate fluid sources.

Signedat Glendale, California, this 5 day and parallel to the adjacent portions of said concave sides whereby said atomizing fluid follows said concave sides and leaves the end of said body portion in a direction substantially parallel to the oil stream issuing from ,said oil discharge slot.

3. An atomizing oil burner head comprising a body portion having an oil discharge slot therein, a passage of oval cross-section leading from said slot, a passage of circular cross-section connecting with said first passage, abafile of circular cross-section positioned between said passages, and resilient means for yieldigly holding said baifle against the end ofsaid passage of circular cross-section.

4. An atomizing oil burner head as described in claim 3 in which the diameter of said baflle is greater than the lesser diameter 7 of said oval passage, but less than the greater diameter thereof.

5. An atomizing oil burner head comprising a body portion having an oil discharge slot in the end thereof and a cylindrical opening laterally disposed from said slot, a tubular bushing fitting in said cylindrical opening and projecting therefrom, the projecting end of said member being closed, a transverse slot in said tubular bushing communicating with the central passage therein and positioned substantially at the surface of said body portion and on the side toward said oil discharge slot, and a source of atomizing fluid connected to the open end of said tubular bushing.

6. An atomizing oil burner head comprising a body portion having an oil discharge slot in the end thereof and a cylindrical opening laterally disposed from said slot, a tubular bushing fitting in said cylindrical opening and projecting therefrom at either end, the end projecting exterior of said burner head being closed and having a transverse slot therein communicating with the central passage in the bushing and positioned substantially at the surface of said body portion and on the sidetowards said oil discharge slot, and the end of said bushing projecting into the interior of said head having an outwardly projecting flange thereon, and a source of atomizing fluid connecting to the inner end of said bushing.

7. An atomizing oil burner head as described in claim 6 having a washer surrounding said tubular bushing and positioned between the outwardly extending flange on said bushing and the body portion of said head;

8. A fluid atomizing and mixing device comprising a body portion having flattened sides concavely tapered to the end, a discharge slot in said end,and a pair of fluid orifices, one on each side of said flattened end directed to discharge fluid along the concaved surfaces 55 of said flattened sides toward said slot, and

of'June, 1931.

' WALTERIA. BABB. 

